December 2, 2024
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What caused this seven-mile scar in the Australian Outback seen on Google Earth?
A man browsing Google Earth discovered a mysterious scar in the Australian outback. And now scientists know what caused it
This Google Earth image shows a mysterious scar etched into the barren Australian landscape.
The following text is reprinted with the user’s permission The conversationan online publication featuring the latest research.
Earlier this year, a speleologist was studying satellite images of the Nullarbor Plain when he came across something unexpected: a huge, mysterious scar etched into the barren landscape.
The findings intrigued scientists, including my colleagues and myself. Upon further investigation, we realized that the scar was created by a vicious tornado that no one knew had happened. In the year we explain the findings new research published today
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Tornadoes are a well-known threat in the United States and elsewhere. But they too happened in Australia.
Without the power of technology, this remarkable example of nature’s toughness would have gone unnoticed. It is important to study the effects of the tornado to help you plan and prepare for the next big twist.
Tornadoes are not just a US phenomenon; They can also happen in Australia.
Gray Zone/Alamy Stock Photo
A history of tornadoes in Australia
Tornadoes They are violent, rotating columns of air that fall to the ground from thunderstorms, and wind speeds often exceed 200 kilometers per hour. They can cause great destruction: uprooting trees, tearing up buildings and throwing debris over great distances.
Tornadoes have occurred on every continent except Antarctica. They occur mostly in the Great Plains region of the United States and in northeastern India-Bangladesh.
The first tornado seen by settlers in Australia occurred in 1795 in the suburbs of Sydney. But Western scientists didn’t confirm a tornado here until the late 1800s.
In recent decades, documented cases in Australia of a The 2013 tornado He crossed north-east Victoria to the New South Wales border. It brought winds of 250-300 kilometers per hour and damaged towns along the Murray River.
And in 2016, a fierce storm arose at least seven tornadoes Central and eastern South Australia.
It’s important for scientists to accurately predict tornadoes so we can issue warnings to communities. This is why the Nullarbor tornado scar was useful to study.
The mystery of the vortex
The Nullarbor Plain is a remote, dry, treeless land in southern Australia. The man who found the scar used Google Earth satellite imagery to search for the Nullabor the caves or other karst features.
Karst is a landscape underlain by limestone with distinctive landforms. The discovery of the scar was brought to the attention of my colleagues and I through a collaborative network of researchers and explorers studying the Nullarbor karst.
The scar stretches across the border from Western Australia to South Australia. It is 20 kilometers from the north Transaustralian railway and 90 kilometers east-northeast of Forrest, a former railway settlement.
We compared satellite images of the site over several years to determine that the tornado occurred between November 16 and 18, 2022. Blue circular patterns appeared near the scar, indicating pools of water associated with heavy rain.
My colleagues and I went to the site in May this year to study and photograph the scar and the surrounding landscape.
These were our results published in the year Journal of Southern Hemisphere Earth Systems Science.
What we found
The scar is 11 kilometers long and 160 to 250 meters wide. It has striking patterns called “cycloidal marks,” which are formed by the suction vortices of tornadoes. This suggests that the tornado was not an ordinary storm, but a powerful one F2 or F3 category, spinning with destructive winds of more than 200 kilometers per hour.
The tornado probably lasted between seven and 13 minutes. The characteristics of the scar suggest that the rotating wind inside the tornado was moving clockwise. We also believe that the tornado moved from west to east, which is consistent with the direction of a strong cold front in the region at the time.
“Cycloids” can be seen in the tornado scars caused by multiple vortices in the Australian outback.
Local weather observations also recorded cloud cover and intensive precipitation during that period in November 2022.
Unlike tornadoes that hit populated areas, this one did not damage homes or towns. But it still left its mark, eroding the soil and vegetation and reshaping the Earth’s surface.
Remarkably, 18 months after the event, the scar was still clearly visible, both on satellite images and on the ground. This is probably because vegetation grows slowly in this dry landscape, so it has not yet covered the erosion.
Plan and prepare
This fascinating discovery on the Nullarbor Plain shows how powerful and unpredictable nature can be, sometimes without us even knowing it.
Only three tornadoes have previously been documented in the Nullarbor Plain. This is likely because the area is remote with few witnesses, and the incidents do not damage property and infrastructure. Interestingly, all three of those tornadoes occurred in November, as did this one.
Our research provides valuable information about tornadoes in this remote and understudied region. It helps us understand when and under what conditions these types of tornadoes occur.
It also emphasizes the importance of satellite imagery to identify and analyze weather phenomena in remote locations, and to help predict and prepare for the next major event.
And finally, the results are a reminder that extreme weather can strike anywhere and anytime.
This article was originally published The conversation. read it original article.
